Introduction: This study evaluated the association between prefecture-level achievement of chronic kidney disease-mineral and bone disorder (CKD-MBD) parameter targets and mortality in Japanese dialysis patients.
Materials and methods: We conducted an ecological study of all prefectures in Japan using data from the Japanese Society of Dialysis Therapy and National Vital Statistics between 2016 and 2017. We calculated adherence rates to recommend target ranges for CKD-MBD parameters, including phosphate, corrected calcium, and parathyroid hormone (PTH), and explored associations of these rates with prefecture-specific standardized mortality rates (SMRs) among the general population and among prevalent dialysis patients using bivariate association analysis and structural equation modeling.
Results: Prefecture-level adherence to the target phosphate range was significantly and negatively associated with prefecture-specific SMRs in men (standardized estimate (β) = - 0.61, p < 0.001) and women (β = - 0.41, p < 0.001). However, prefecture-level adherence to the target corrected calcium range was significantly and negatively associated with prefecture-specific SMRs only in men (β = - 0.28, p = 0.01). Meanwhile, prefecture-level adherence to the target PTH range was significantly and positively associated with prefecture-specific SMRs in men (β = 0.23, p = 0.04). Prefecture-level SMRs of females in the general population had a significant impact on prefecture-level SMRs of female dialysis patients (β = 0.27, p = 0.03). The models explained 52% of variance in SMR for men and 33% for women.
Conclusion: A higher prefecture-level achievement rate of the target phosphate range recommended by the Japanese CKD-MBD guidelines was associated with a lower prefecture-specific SMR in the Japanese dialysis population.
Keywords: CKD-MBD; Dialysis; Ecological study; Regional variation; Standardized mortality ratio.
© 2022. The Japanese Society Bone and Mineral Research.